A Comparative Study of Harmonic Distortion in Multicarrier Based PWM Switching Techniques for Cascaded H-Bridge Inverters

作者：Hamedani Pegah^*; Shoulaie Abbas

来源：Advances in Electrical and Computer Engineering, 2016, 16(3): 15-24.

DOI：10.4316/AECE.2016.03003

• converters
• harmonic distortion
• inverters
• modulation
• pulse width modulation

Multicarrier based PWM switching patterns are commonly utilized to control Cascaded H-bridge (CHB) inverters. The main contribution of this paper is to comprehensively investigate the effect of various multicarrier based PWM techniques on harmonic content of the CHB multilevel inverter. In order to achieve this, both of the CHB output voltage and the input current at power grid side have been taken into account. In this work, various PWM modulations such as level shifted (LS), phase shifted (PS), hybrid, and rotative-LS (R-LS) have been studied through both simulation and implementation of an experimental setup. By extracting the frequency spectrum and calculation of THD and WTHD indices, a quantitative comparative study of various multicarrier PWM techniques has been carried out. According to the results, the R-LS-PWM methods (i.e. R-PD, and two new proposed R-POD and R-APOD) reduce the harmonic distortion of the input current while keeping the obvious advantage of LS-PWM modulation such as lower harmonic distortion of the output voltage. Specially, the proposed R-APOD-PWM modulation offers these preferable privileges at odd frequency ratio values.

• 出版日期2016